How the Stock Portfolio works:
This example demonstrates Server to Server communication using SOAP as the
mechanism to retrieve remote information - in this case stock quotes in the form
of an object that contains the quote data. When you hit Refresh on this page the
Web Server is accessed and the
current portfolio's symbols are gathered into an XML string. This string is then
passed as a parameter to the SOAP Web Service that provides the stock quote
functionality. The GetStockQuotes Web Service method then goes out and internally
calls the GetStockQuote method which returns a single object repeatedly until
all quotes have been retrieved. In this case the SOAP Web Service also runs on
the West Wind site, but it could potentially run elsewhere. The actual quotes are retrieved
from yet another server on the NASDAQ
site also served in XML format.
The resulting quotes are then turned into an XML string and returned as part of the SOAP call via return parameter to the client application (this Web page's server code). The code takes the result XML parameter and re-creates the indivdual quote objects and updates the portfolio with this data. The app then displays and recalculates the entire portfolio here. You can take a look at the server side code that performs the SOAP client call and the Web Service on the SOAP server that makes the calls to the NASDAQ site.
How the single stock quote works:
This example uses
JScript code to call the same SOAP Web Service to retrieve a single stock quote
using the GetStockQuote() method. The method returns an Object parameter, which
is returned to the JScript code as an XML string. The XML is loaded into the
XMLDOM and then uses selectSingleNode() to retrieve the values to
display from the object. An HTML string is built and substituted directly into
this document below the quote textbox.
You can view source to see the GetStockQuote() function in this page, and look at wwsoap.js, which is a very basic SOAP client.